Dielectric spectroscopy of porous HCl-doped polyaniline containing lanthanum ions

HCl-doped polyaniline containing lanthanum ions were synthesized by the chemical oxidizing of aniline in the presence of aqueous acidic salt solution, with different concentrations of lanthanum chloride. The effects of the concentration of La3+ on the morphology and dielectric properties of the prepared samples were investigated by scanning electron microscopy (SEM) and dielectric measurements. The SEM micrographs revealed that the HCl-doped polyaniline had an aggregated structure, while the HCl-doped samples containing La3+ ions presented a distinct morphology with porous structures. For the samples, both epsilon' and epsilon '' exhibited a relatively high value at low frequency and a sharp decrease with increasing frequency. Increasing the concentration of La3+ resulted in a significant enhancement of epsilon' and epsilon ''.